JP5390869B2 - Laminated iron core and method for manufacturing the same - Google Patents

Description

The present invention relates to a laminated core in which adjacent segment core pieces are connected by a bent connecting portion, and a method for manufacturing the laminated core.

Conventionally, in order to improve the yield of a core material (for example, a strip) used for manufacturing a laminated core, when punching a core piece from the core material, for example, as described in Patent Document 1, it is not annular. A plurality of segment core pieces continuous in a strip shape are formed by punching, and the segment core pieces are formed in a strip shape as described in the so-called wound cores for manufacturing a laminated core by winding and stacking them. A so-called Poki Poki core is known in which a laminated iron core is manufactured by laminating as it is and bending it into a circle.

Specifically, in any laminated iron core, a segment core piece on an arc having a predetermined number of slots is connected to each other via a connecting portion, and then a mold is made from an iron core material (strip material). Punch with. And while bending the connecting portion formed on the outer peripheral side and aligning the side end portions of the adjacent segment core pieces, a plurality of continuous segment core pieces are spirally wound and stacked, or a plurality of strips are connected in a strip shape A predetermined number of segment core pieces are stacked, the connecting portion is bent, and the side ends of adjacent segment core pieces are joined together to form an annular shape.

Japanese Patent Laid-Open No. 1-264548 JP-A-8-196061 Japanese Patent No. 3171303

However, in any of Patent Documents 1 to 3, when a connecting portion is bent to arrange a plurality of segment core pieces in an annular shape, a bulging portion is generated in the thickness direction of the connecting portion, and this bulging portion is laminated. As a result, gaps were generated between the segmented iron core pieces, causing variations in the thickness of the manufactured laminated iron core. For example, in the assembly of a motor using a laminated iron core, this gap requires an extra processing for eliminating the gap and causes a reduction in efficiency or vibration of the motor, which adversely affects the quality of the motor.

Further, in recent years, when the connecting portion 61 having one notch recess 60 as shown in FIG. 6 (A) is bent as shown in FIG. As shown in FIG. 6B, plastic deformation accompanied by thickness reduction occurs in the radially outer region 62a of the bending start point 62 of the connecting portion 61, and a cut 63 and a crack as shown in FIG. It was a factor that reduced accuracy. 6 (A) to 6 (C), 64 is an outer notch, and 65 and 66 are segment core pieces.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a laminated core capable of manufacturing a high-quality product with high efficiency while suppressing the bulging of the connecting portion in the thickness direction, and a method for manufacturing the same.

The laminated core according to the first aspect of the present invention, wherein the segment core pieces adjacent to each other are connected to each other at a connecting portion formed radially inward from the radially outer end of the segment core pieces. In the laminated core formed by forming the core piece into an annular shape by bending the connecting portion,
A plurality of bent portions (for example, two, three, or more) are formed in the connecting portion by forming a notch recess radially inward to partially narrow the radial width , and each of the bent portions is provided . Is provided with the notch recess having an arc shape with the same radius of curvature radially inside, and the radial length of the center of the bent portion is the same,
One tensile force generation region is formed on the radially outer side of the connecting portion by the plurality of bent portions formed in the connecting portion.
As a result, the stress generated when the connecting portion is bent is relaxed or substantially uniformly distributed in the plurality of bent portions.

In this way, by providing a plurality of bent portions, the bending angle can be dispersed into a plurality of portions, and an increase in the plate thickness that occurs inside the connecting portion in the radial direction when the connecting portion is bent is reduced. In addition, a tensile force is generated on the outer side in the radial direction of the connecting portion. However, since this tensile force is also dispersed in the plurality of bent portions, the “cut” that occurs when the plate thickness is excessively reduced is less likely to occur.

In addition, each of the bent portions includes the notch concave portion having an arc shape with the same radius of curvature on the radially inner side, and the length in the radial direction of the center of the bent portion is the same. Thereby, when a bending load is applied to the connecting portion, the bending force is easily dispersed in the plurality of bending portions.

A laminated iron core according to a second aspect of the invention is a laminated iron core according to the first aspect of the invention, wherein a radius generated when the connecting part is bent is radially outward of the connecting part in which the plurality of bent parts are formed. An outer notch is provided in which the direction bulging portion is accommodated in the outer circle (outer circle) of the laminated iron core.
As a result, the radially bulging portion is accommodated within the outer circle of the laminated core that is the product.

Laminated core according to a third aspect is the laminated core according to the first, the second invention, the connecting portion has the bent portions at two locations, the center folding position of the folding portion passes through the connecting portion It is formed symmetrically with respect to the radial center line. Accordingly, when the connecting portion is bent, each bent portion causes uniform deformation.

In the laminated core according to the fourth aspect of the present invention, in the laminated cores according to the first to third aspects of the invention, each bent portion of the connecting portion has a bending start point , and a compressive stress is generated in a radially inner region of the bending start point. It depends. Depending on the shape of the connecting portion, the bending start point may not be generated and the connecting portion may be bent. In the present invention, plastic deformation occurs and the connecting portion is clearly generated when the bending starting point is generated.

A method for manufacturing a laminated core according to a fifth aspect of the present invention is a method for manufacturing a laminated core in which a plurality of segment core pieces, in which adjacent segment core pieces are connected to each other at a connecting portion, are formed into an annular shape by bending the connecting portion. In
When forming the segment core piece, an outer notch is formed on the outer side in the radial direction of the connecting portion so that a radially bulging portion formed on the outer side in the radial direction when the connecting portion is bent is accommodated in the outer circle of the laminated core. And a process of
A plurality of notches recess an arc shape with the same radius of curvature for forming the respective connecting portions bent portion have a forming radially inwardly of the connecting portion,
When the plurality of bent portions formed in the connecting portion are bent, one tensile force generation region is formed on the radially outer side of the connecting portion .

And the manufacturing method of the laminated core which concerns on 6th invention is a manufacturing method of the laminated core which concerns on 5th invention. WHEREIN: The connection part which has the said notch recessed part is right and left with respect to the radial direction centerline of this connection part. It is formed symmetrically.

In the present invention, the segment core pieces connected at the connecting portion are continuous, and are gradually bent at the connecting portion, and a plurality of segment core pieces are spirally wound to form a predetermined core connected at the connecting portion. The present invention is also applicable to a laminated iron core (so-called “pokipoki core”) in which a number of segment iron core pieces are laminated and the laminated continuous segment pieces are bent at a connecting portion.

In the laminated core and the method for manufacturing the same according to the present invention, a plurality of bent portions in which notches are formed on the radially inner side and the radial width is partially narrowed in the connecting portions that connect the segment core pieces. Since it is provided, the stress generated when the connecting portion is bent is distributed substantially evenly at the plurality of bent portions. As a result, the bulge portion in the thickness direction formed on the inner side in the radial direction of the connecting portion can be reduced, and the gap between the core pieces in the stacking direction can be reduced when stacking the core pieces, so that the motor can be highly efficient. At the same time, motor quality can be improved by preventing vibration.

In addition, since it is possible to prevent the occurrence of breaks and cracks when the connecting portion is bent, it is possible to prevent a decrease in productivity due to an obstacle such as facility stoppage.
And, in the case of Poki Poki core in which a plurality of segment core pieces are laminated as they are, since they are formed into an annular shape after being laminated in a band shape, the amount of bulging of the connecting portion escaping from the laminating direction to the circumferential direction when repressurizing is reduced Thus, the efficiency of the motor can be increased.

(A) is a top view of the laminated iron core which concerns on the 1st Embodiment of this invention, (B) is a side view of the laminated iron core. It is a fragmentary top view of the continuous segment piece of the same laminated iron core. It is an enlarged plan view of the connection part of a segment core piece. It is an enlarged plan view of the connection part of the laminated iron core which concerns on the 2nd Embodiment of this invention. It is an enlarged plan view of the connection part of the laminated iron core which concerns on the 3rd Embodiment of this invention. (A)-(C) are the partially expanded plan views of the laminated iron core which concerns on a prior art example.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
As shown in FIGS. 1 (A) and 1 (B), the laminated core 10 according to the first embodiment of the present invention is composed of a wound core, and the thicknesses connected by the connecting portions 11 are, for example, 0. A long continuous segment piece 13 (see FIG. 2) composed of a plurality of segment core pieces 12 of 1 to 0.5 mm is connected to a connecting portion 11 formed radially inward from the radially outer end of the segment core piece 12. Sequential bending is performed, and the inner magnetic pole piece portions 14 are wound while being aligned in the vertical direction, and formed into an annular shape. Each segment core piece 12 is joined in the vertical direction by caulking, welding, or adhesion (the same applies to the following embodiments).

Each segment core piece 12 includes a yoke piece portion 15 on the radially outer side and a plurality (three in this embodiment) of magnetic pole piece portions 14 on the inner side.
Each connecting portion 11 has an outer notch 17 formed symmetrically with respect to the center line k1 on the outer side in the radial direction, and an arc-shaped notch recess 18 with the same radius of curvature symmetrically with respect to the center line k1 on the inner side. 19 is formed. The center line k 1 is a radial center line passing through the center of the laminated core 10.

As shown in FIGS. 1 and 3, the outer notch 17 formed on the outer side in the radial direction of the connecting part 11 and the notch recesses 18 and 19 formed on the inner side in the radial direction of the connecting part 11 have a radius on the connecting part 11. A plurality of (two in this example) bent portions 20 and 21 formed by a portion having the shortest direction width are formed. The lengths in the radial direction of the centers of the bent portions 20 and 21 are the same.
In addition, the semicircular notch 24 which is an example of an engagement recessed part and the semicircle protrusion 25 which is an example of an engagement convex part are formed in the side end parts 22 and 23 of the circumferential direction of each segment iron core piece 12, respectively. When the segment core piece 12 is wound (see FIG. 2), adjacent semicircular protrusions 25 are fitted in the semicircular notches 24. In addition, this engagement recessed part and engagement convex part can also be abbreviate | omitted.

The adjacent segment core pieces 12 may be wound on the circumference with a small gap between the side end portions 22 and 23, or the segment core piece 12 may be wound with the side end portions 22 and 23 in close contact with each other. May be. Note that the number of magnetic poles n (20 in this embodiment) of the laminated core 10 is not a multiple of the number m (3 in this embodiment) of the magnetic pole pieces 14 of each segment core piece 12 and is continuous. When the segmented iron core piece 12 is wound, the upper and lower connecting portions 11 are not overlapped.

A slot 26 is formed between the magnetic pole pieces 14 of each segment core piece 12. The present invention is also applied to the case where a recess into which all of the connecting portions 11 of the segment core pieces 12 adjacent to each other are provided in the yoke piece portion 15 radially outside the slot 26 is applied. Since the cross-sectional area is reduced, the magnetic characteristics are somewhat deteriorated, but there is an advantage that even if the connecting portion 11 bulges in the thickness direction, the overall thickness of the laminated core 10 is not affected.

In the laminated iron core 10 according to this embodiment, since a plurality of bent portions 20 and 21 are formed in the connecting portion 11, when the connecting portion 11 is bent, as shown in FIG. Bending start points 29 and 30 are formed at the center position in the radial direction, and a tensile force generating region (shown by hatching) is formed on the radially outer side of the bending starting points 29 and 30, and a compressive force generating region is formed on the radially inner side.

If the stress in the tensile force generation region is large, the connecting portion 11 is cut or cracked. In this embodiment, however, it is generated because a plurality of bent portions 20 and 21 are formed in one connecting portion 11. Stress is dispersed and reduced, and cuts and cracks are less likely to occur.
Further, in the compressive force generation region, the thickness increases, but since the plurality of bent portions 20 and 21 are formed in one connecting portion 11, the increase in thickness is negligible.

Accordingly, the connecting portion 11 is bent at each of the bent portions 20 and 21, and as a result, the bending angle of each of the bent portions 21 and 22 is small, and accordingly, the bulge in the thickness direction formed inside the connecting portion 11 in the radial direction. Even when the upper and lower segment core pieces 12 have no recesses that allow the bulging portions to escape, the upper and lower adjacent gaps between the segment core pieces 12 of the laminated core 10 due to the bending of the connecting portion 11 are reduced. Can be small.

In this embodiment, the two bent portions 20 and 21 are formed in the connecting portion 11, but three or four or more bent portions can be formed in one connecting portion 11. In this case, what is important is to form the bent portions uniformly and bend the bent portions evenly when the connecting portion 11 is bent.
Moreover, in the said embodiment, although the bending start point was a point, the whole bending stress can be made small and a buckling of material can be prevented and it can also be made into circular arc shape.

Then, the manufacturing method of the laminated core 10 which concerns on the 1st Embodiment of this invention is demonstrated, referring FIGS. 1-3.
As shown in FIG. 2, the laminated core 10 is manufactured by pressing a continuous segment piece 13 in which the segment core piece 12 is connected to a magnetic strip 31 wider than the width of each segment core piece 12 by a connecting portion 11 as shown in FIG. Form. One segment core piece 12 has a plurality of magnetic pole piece portions 14 and a yoke piece portion 15 for connecting them.

In the production of the laminated core 10, when the plurality of segment core pieces 12 connected by the connecting portion 11, that is, the continuous segment pieces 13 are formed, the connecting portion 11 is bent outwardly in the radial direction of the connecting portion 11. A step of forming an outer notch 17 for accommodating a radially bulging portion that is sometimes formed on the outer side in the radial direction within an outer circle (outer circle) 31a of the laminated iron core 10, and bending portions 20 and 21 are formed in the connecting portion 11, respectively. Forming notch recesses 18 and 19 having the same shape on the radially inner side of the connecting portion 11.

When the continuous segment piece 13 is spirally wound around an axis having a large diameter within a range slightly smaller than the rotor, the continuous segment piece 13 is bent at each connecting portion 11. In this case, since one connecting portion 11 has a plurality of bent portions 20 and 21, stress is dispersed rather than bending the connecting portion with one bent portion, and no cut or crack occurs in the tensile force generation region. In the compressive force generation region, the increase in thickness is reduced.

Next, the laminated core 32 according to the second embodiment of the present invention shown in FIG. 4 will be described. In this embodiment, a plurality of arc-shaped cutout recesses 35 and 36 are provided in the outer cutout 34 of the connecting portion 33 that connects the adjacent segment core pieces 12, and the inner portion of the connecting portion 33 is also described above. A plurality of inner notch recesses 37 and 38 corresponding to the outer notch recesses 35 and 36 are provided. A plurality of bent portions 39, 40 are formed between the inner and outer cutout recesses 35, 37 and the cutout recesses 36, 38 that form a pair. By forming in this way, a plurality of bent portions 39, 40 are formed in one connecting portion 33, so that the stress generated in the connecting portion 33 when the continuous segment piece is bent is relieved.

Further, in the laminated core 42 according to the third embodiment of the present invention shown in FIG. 5, arc-shaped cutout recesses 45 and 46 are formed in the outer cutout 44 formed in the connection portion 43, and the connection is made. A notch recess corresponding to these notch recesses 45 and 46 is not provided in an inner notch 47 formed radially inward of the portion 43. However, since a region having a minimum radial width is formed between the notch recesses 45 and 46 formed on the outer side and the inner notch 47, this portion forms the bent portions 48 and 49.

Therefore, when the connecting portion 43 is bent, it is bent at a plurality of bent portions 48 and 49, and the stress at the time of bending is dispersed. Therefore, it is difficult for the outer region of the connecting portion 43 to be cut or cracked, and the inner region is increased in thickness. Less.
The manufacturing method of the laminated core according to the second and third embodiments is the same as the manufacturing method of the laminated core according to the first embodiment, except that the configuration of the connecting portion is different.

In the above-described embodiment, the laminated core composed of the wound cores and the manufacturing method thereof have been described. However, the number of the total magnetic pole pieces of the continuous segment pieces matches the number n of magnetic poles of the laminated cores. Or, each segment core piece has a plurality of magnetic pole pieces, and each segment core piece is laminated with a continuous segment piece connected with a foldable connecting portion to produce an intermediate laminated core closer to a straight line. The present invention is also applicable to a laminated iron core (so-called “poki-poki core”) that is bent into a ring shape.

Moreover, in the said embodiment, although the stator lamination | stacking iron core was demonstrated, this invention is applied even if it is a rotor lamination | stacking iron core which has a magnetic pole outside.

10: laminated iron core, 11: connecting portion, 12: segment core piece, 13: continuous segment piece, 14: magnetic pole piece portion, 15: yoke piece portion, 17: outer notch, 18, 19: notch recess, 20, 21: bent portion, 22, 23: side end portion, 24: semicircular notch, 25: semicircular protrusion, 26: slot, 29, 30: bending start point, 31: magnetic strip, 31a: outer circle, 32: Laminated core, 33: connecting portion, 34: outer notch, 35, 36: notched recess, 37, 38: notched recess, 39, 40: bent portion, 42: laminated core, 43: connecting portion, 44: outside Notch, 45, 46: Notch recess, 47: Inner notch, 48, 49: Bent

Claims (6)

A plurality of the segment core pieces, in which adjacent segment core pieces are connected to each other at a connecting portion formed radially inward from the radially outer end of the segment core piece, are formed in an annular shape by bending the connecting portion. In the laminated iron core,
The connecting portion is provided with a plurality of bent portions, each having a notch concave portion formed radially inward and partially narrowed in the radial direction , and each bent portion has an arc shape with the same radius of curvature radially inward. The notched concave portion, and the radial length of the bent portion center is the same,
The laminated iron core is characterized in that one tensile force generation region is formed on the radially outer side of the connecting portion by a plurality of bent portions formed in the connecting portion . 2. The laminated core according to claim 1 , wherein a radially bulging portion generated when the connecting portion is bent is provided on an outer side of the laminated core on a radially outer side of the connecting portion where the plurality of bent portions are formed. A laminated iron core characterized in that an outer notch is provided in a circle. 3. The laminated core according to claim 1 , wherein the connecting portion has two bent portions, and a bending center position of the bent portion is formed symmetrically with respect to a radial center line passing through the connecting portion. A laminated iron core characterized by The laminated core according to any one of claims 1 to 3 , wherein each bent portion of the connecting portion has a bending start point , and a compressive stress is applied in a region radially inward of the bending start point. Laminated iron core. In the method of manufacturing a laminated core, wherein a plurality of the segment core pieces, in which adjacent segment core pieces are connected to each other at a connecting portion, are formed in an annular shape by bending the connecting portion.
When forming the segment core piece, an outer notch is formed on the outer side in the radial direction of the connecting portion so that a radially bulging portion formed on the outer side in the radial direction when the connecting portion is bent is accommodated in the outer circle of the laminated core. And a process of
A plurality of notches recess an arc shape with the same radius of curvature for forming the respective connecting portions bent portion have a forming radially inwardly of the connecting portion,
A method of manufacturing a laminated iron core , wherein one tensile force generation region is formed on a radially outer side of the connecting portion when the plurality of bent portions formed in the connecting portion are bent . 6. The method of manufacturing a laminated core according to claim 5 , wherein the connecting portion having the notch recess is formed symmetrically with respect to a radial center line of the connecting portion. .

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